The sharp decline in coal demand over the last few years has forced the big freight carrier off onto a siding. It looks to be heading back onto a main track and powering ahead.

The biggest railroad in the Eastern U.S., CSX, has been chugging along for an extended stretch with a bum engine. Demand for coal, a key revenue and profit generator, has dropped sharply in recent years, forcing the company to devise new ways to keep pushing its profits higher. Now the likelihood of more-stable coal demand, coupled with the company's operating improvements, have put the rail operator's shares on an upward path that could have a long way to run.